Here is a bag that holds it shape . 100% waterproof with a hard sheet with 4 pockets on the inside.
With a beautiful flame design these bags measure 14" x 6" x 10"

Easy on/off bag w/ heavy duty velcro cover
Universal fitting. Heavy duty Q-Release.
With UV protection the bag will not turn white in extreme heat.For extra security the bag has four tie down ribbins on each side